When you try to sign in to an Office 2016 for Mac app by using your Office 365 user ID and password, you receive the following error message:
Sorry, another account from your organization is already signed in on this computer.
To resolve this issue, use the Keychain Access app to delete any password entries that contain "Office." To do this, follow these steps:
Start the Keychain Access app.
In the Search field, type Office.
Delete any entries that are found.
Note You should find between two and six entries.
Exit the Keychain Access app, and then try to sign in to Office 2016 for Mac again.
This behavior is expected. It occurs if you're already signed in to Office 2016 for Mac through a different Office 365 user account in the same organization.
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